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<div class="titlepage"><div><div><h5 class="title">
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb"></a><a class="link" href="larrb.html" title="larrb">larrb</a>
</h5></div></div></div>
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.prototype"></a><h6>
<a name="id1084612"></a>
            <a class="link" href="larrb.html#boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.prototype">Prototype</a>
          </h6>
<p>
            There is one prototype of <code class="computeroutput"><span class="identifier">larrb</span></code>
            available, please see below. 
</p>
<pre class="programlisting"><span class="identifier">larrb</span><span class="special">(</span> <span class="keyword">const</span> <span class="identifier">int_t</span> <span class="identifier">n</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">VectorD</span><span class="special">&amp;</span> <span class="identifier">d</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">VectorLLD</span><span class="special">&amp;</span> <span class="identifier">lld</span><span class="special">,</span>
        <span class="keyword">const</span> <span class="identifier">int_t</span> <span class="identifier">ifirst</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">int_t</span> <span class="identifier">ilast</span><span class="special">,</span>
        <span class="keyword">const</span> <span class="identifier">Scalar</span> <span class="special">&gt;,</span> <span class="keyword">const</span> <span class="identifier">Scalar</span> <span class="special">&gt;,</span> <span class="keyword">const</span> <span class="identifier">int_t</span> <span class="identifier">offset</span><span class="special">,</span>
        <span class="identifier">VectorW</span><span class="special">&amp;</span> <span class="identifier">w</span><span class="special">,</span> <span class="identifier">VectorWGAP</span><span class="special">&amp;</span> <span class="identifier">wgap</span><span class="special">,</span> <span class="identifier">VectorWERR</span><span class="special">&amp;</span> <span class="identifier">werr</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">Scalar</span> <span class="special">&gt;,</span>
        <span class="keyword">const</span> <span class="identifier">Scalar</span> <span class="special">&gt;,</span> <span class="keyword">const</span> <span class="identifier">int_t</span> <span class="identifier">twist</span> <span class="special">);</span>
</pre>
<p>
          </p>
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.description"></a><h6>
<a name="id1084994"></a>
            <a class="link" href="larrb.html#boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.description">Description</a>
          </h6>
<p>
            <code class="computeroutput"><span class="identifier">larrb</span></code> (short for $FRIENDLY_NAME)
            provides a C++ interface to LAPACK routines SLARRB and DLARRB. Given
            the relatively robust representation(RRR) L D L^T, <code class="computeroutput"><span class="identifier">larrb</span></code>
            does "limited" bisection to refine the eigenvalues of L D L^T,
            W( IFIRST-OFFSET ) through W( ILAST-OFFSET ), to more accuracy. Initial
            guesses for these eigenvalues are input in W, the corresponding estimate
            of the error in these guesses and their gaps are input in WERR and WGAP,
            respectively. During bisection, intervals [left, right] are maintained
            by storing their mid-points and semi-widths in the arrays W and WERR
            respectively.
          </p>
<p>
            The selection of the LAPACK routine is done during compile-time, and
            is determined by the type of values contained in type <code class="computeroutput"><span class="identifier">VectorD</span></code>.
            The type of values is obtained through the <code class="computeroutput"><span class="identifier">value_type</span></code>
            meta-function <code class="computeroutput"><span class="keyword">typename</span> <span class="identifier">value_type</span><span class="special">&lt;</span><span class="identifier">VectorD</span><span class="special">&gt;::</span><span class="identifier">type</span></code>. The dispatching table below illustrates
            to which specific routine the code path will be generated.
          </p>
<div class="table">
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.dispatching_of_larrb"></a><p class="title"><b>Table&#160;1.347.&#160;Dispatching of larrb</b></p>
<div class="table-contents"><table class="table" summary="Dispatching of larrb">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Value type of VectorD
                    </p>
                  </th>
<th>
                    <p>
                      LAPACK routine
                    </p>
                  </th>
</tr></thead>
<tbody>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="keyword">float</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      SLARRB
                    </p>
                  </td>
</tr>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="keyword">double</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      DLARRB
                    </p>
                  </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break"><a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.definition"></a><h6>
<a name="id1085242"></a>
            <a class="link" href="larrb.html#boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.definition">Definition</a>
          </h6>
<p>
            Defined in header <code class="computeroutput">boost/numeric/bindings/lapack/auxiliary/larrb.hpp</code>.
          </p>
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.parameters_or_requirements_on_types"></a><h6>
<a name="id1085282"></a>
            <a class="link" href="larrb.html#boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.parameters_or_requirements_on_types">Parameters
            or Requirements on Types</a>
          </h6>
<div class="variablelist">
<p class="title"><b>Parameters</b></p>
<dl>
<dt><span class="term">MatrixA</span></dt>
<dd><p>
                  The definition of term 1
                </p></dd>
<dt><span class="term">MatrixB</span></dt>
<dd><p>
                  The definition of term 2
                </p></dd>
<dt><span class="term">MatrixC</span></dt>
<dd>
<p>
                  The definition of term 3.
                </p>
<p>
                  Definitions may contain paragraphs.
                </p>
</dd>
</dl>
</div>
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.complexity"></a><h6>
<a name="id1085370"></a>
            <a class="link" href="larrb.html#boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.complexity">Complexity</a>
          </h6>
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.example"></a><h6>
<a name="id1085395"></a>
            <a class="link" href="larrb.html#boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.example">Example</a>
          </h6>
<p>
            
</p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">numeric</span><span class="special">/</span><span class="identifier">bindings</span><span class="special">/</span><span class="identifier">lapack</span><span class="special">/</span><span class="identifier">auxiliary</span><span class="special">/</span><span class="identifier">larrb</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">bindings</span><span class="special">;</span>

<span class="identifier">lapack</span><span class="special">::</span><span class="identifier">larrb</span><span class="special">(</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">y</span><span class="special">,</span> <span class="identifier">z</span> <span class="special">);</span>

</pre>
<p>
          </p>
<p>
            this will output
          </p>
<p>
            
</p>
<pre class="programlisting"><span class="special">[</span><span class="number">5</span><span class="special">]</span> <span class="number">0</span> <span class="number">1</span> <span class="number">2</span> <span class="number">3</span> <span class="number">4</span> <span class="number">5</span>
</pre>
<p>
          </p>
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.notes"></a><h6>
<a name="id1085681"></a>
            <a class="link" href="larrb.html#boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.notes">Notes</a>
          </h6>
<a name="boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.see_also"></a><h6>
<a name="id1085706"></a>
            <a class="link" href="larrb.html#boost_numeric_bindings.reference.lapack.auxiliary_routines.larrb.see_also">See
            Also</a>
          </h6>
<div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem">
                Originating Fortran source files <a href="http://www.netlib.org/lapack/single/slarrb.f" target="_top">slarrb.f</a>
                and <a href="http://www.netlib.org/lapack/double/dlarrb.f" target="_top">dlarrb.f</a>
                at Netlib.
              </li></ul></div>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer">Copyright &#169; 2002 -2009 Rutger ter Borg, Kre&#353;imir Fresl, Thomas Klimpel,
      Toon Knapen, Karl Meerbergen<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
</div></td>
</tr></table>
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